Guggulsterone induces apoptosis of human hepatocellular carcinoma cells through intrinsic mitochondrial pathway

AIM: To investigate the effects of guggulsterone on the proliferation and apoptosis of human hepatoma Hep G2 cells in vitro and relevant mechanisms.METHODS: Human hepatocellular carcinoma Hep G2 cells and normal human liver L-02 cells were treated with different concentrations of guggulsterone(5-100 μmol/L) for 24-72 h. Cell proliferation was tested by MTT assay. Cell cycle and apoptosis were investigated using flow cytometry(FACS). Bcl-2 and Bax m RNA and protein expression was detected by real-time PCR and Western blot, respectively. TGF-β1, TNF-α, and VEGF contents were determined by ELISA.RESULTS: Guggulsterone significantly inhibited Hep G2 cell proliferation in a dose- and time-dependent manner. FACS showed that guggulsterone arrested Hep G2 cell cycle at G0/G1 phase. Guggulsterone induced apoptosis was also observed in Hep G2 cells, with 24.91% ± 2.41% and 53.03% ± 2.28% of apoptotic cells in response to the treatment with 50 μmol/L and 75 μmol/L guggulsterone, respectively. Bax m RNA and protein expression was significantly increased and Bcl-2 m RNA and protein expression was decreased. ELISA analysis showed that the concentrations of TGF-β1 and VEGF were significantly decreased and TNF-α concentration was increased.CONCLUSION: Guggulsterone exerts its anticancer effects by inhibiting cell proliferation and inducing apoptosis in Hep G2 cells. Guggulsterone induces apoptosis by activation of the intrinsic mitochondrial pathway.

Amiloride and guggulsterone suppression of esophageal cancer cell growth in vitro and in nude mouse xenografts

Esophageal adenocarcinoma is increasing in the US and Western countries and frequent gastresophageal reflux or gastresophageal reflux disease carrying gastric acid and bile acid could contribute to esophageal adenocarcinogenesis. This study was designed to detect the expression of gastric acid-inducing gene Na＋/H＋ exchanger-1 （NHE-1） ex vivo and then to explore targeting of NHE-1 expression or activity to control esophageal cancer cell viability in vitro and in nude mouse xenografts. The data showed that NHE-1 was highly expressed in esophageal adenocarcinoma tissues （66 of 101 cases [65.3%｜, but not in normal esophageal squamous cell epithelium （1 of 26 cases [3.8~0]）. Knockdown of NHE-1 expression using NHE-1 shRNA or inhibition of NHE-1 activity using the NHE-1 inhibitor amiloride suppressed viability and induced apoptosis in esophageal cancer cells. Molecularly, amiloride inhibited expression of cyclooxygenase-2 and matrix metallopeptidase-9 but not NHE-1 mRNA in esophageal cancer cells. A combination of amiloride and guggulsterone （a natural bile acid receptor inhibitor） showed more than additive effects in suppressing esophageal cancer cell growth in vitro and in nude mouse xenografts. This study suggests that inhibition of NHE-1 expression or activity or combination of amiloride and guggulsterone could be useful in control of esophageal adenocarcinoma.

Natural compounds as potential inhibitors of SARS-CoV-2 main protease: An insilico study

Objective:To explore natural compounds as potential inhibitors against main protease(Mpro)of SARS-CoV-2.Methods:In the current study,systematic molecular docking analysis was conducted using AutoDock 4.2 to determine the binding affinities and interactions between natural compounds and Mpro.Selected natural compounds were further validated using a combination of molecular dynamic(MD)simulations and molecular mechanic Poisson-Boltzmann surface area(MM/PBSA)free energy c alculation s.Results:Out of twenty natural compounds,four natural metabolites namely,amentoflavone,guggulsterone,puerarin,and piperine were found to have strong interaction with Mpro of SARS-CoV-2 based on docking analysis.During MD simulations,all four natural compounds bound to Mpro at 50 ns and MM/G/P/BSA free energy calculations showed that all four shortlisted ligands had stable and favorable energies with strong binding to Mpro protein.Conclusions:Guggulsterone is a potential inhibitor of COVID-19 main protease Mpro.Further in vitro and pre-clinical studies are needed.